1. 首先，需要在项目中导入 Admob SDK。可以使用 CocoaPods 或手动下载和导入 SDK。
2. 在项目的 Info.plist 文件中添加 Admob 应用程序 ID。
3. 引入 GoogleMobileAds 库并创建一个广告单元 ID。

import SwiftUI
import GoogleMobileAds

final class AdmobRewarded: NSObject, GADRewardedAdDelegate {
    private var rewardedAd: GADRewardedAd?

    func loadAd() {
        GADRewardedAd.load(
            withAdUnitID: "",
            request: GADRequest(),
            completionHandler: { [weak self] ad, error in
                guard let self = self else { return }
                if let error = error {
                    print("Rewarded ad failed to load with error: \(error.localizedDescription)")
                    return
                }
                self.rewardedAd = ad
                self.rewardedAd?.fullScreenContentDelegate = self
            }
        )
    }

    func showAd() {
        if let ad = rewardedAd {
            ad.present(fromRootViewController: UIApplication.shared.windows.first?.rootViewController ?? UIViewController())
        } else {
            print("The rewarded ad wasn't ready yet.")
        }
    }

    func rewardedAd(_ rewardedAd: GADRewardedAd, userDidEarn reward: GADAdReward) {
        print("Reward received with currency: \(reward.type), amount \(reward.amount).")
    }

    func rewardedAdDidDismissFullScreenContent(_ rewardedAd: GADRewardedAd) {
        self.loadAd()
    }
}

4. 在 ContentView 中创建一个 AdmobRewarded 实例，并调用 loadAd() 和 showAd() 方法以在需要时显示激励广告。

struct ContentView: View {
    let rewardedAd = AdmobRewarded()

    var body: some View {
        VStack {
            Text("Hello, World!")
            Button("Show rewarded ad") {
                rewardedAd.showAd()
            }
        }
        .onAppear {
            rewardedAd.loadAd()
        }
    }
}